First flush reactor for stormwater treatment for elevated linear transportation projects.

Details

• Creators:
  Deng, Zhi-Qiang
• Corporate Creators:
  Louisiana State University. Department of Civil and Environmental Engineering
• Corporate Contributors:
  United States. Federal Highway Administration
• Subject/TRT Terms:
  • Drainage structures
  • Water pollution
  • Runoff
  • Water--Pollution--Research--Louisiana
  • Elevated highways
  • Runoff
• Publication/ Report Number:
  FHWA/LA.08/466
• Resource Type:
  Tech Report
• Geographical Coverage:
  Louisiana
• Edition:
  Final report; Dec. 2007-May 2009.
• Corporate Publisher:
  Louisiana Transportation Research Center
• Abstract:
  The United States EPA (Environmental Protection Agency) MS4 (Municipal Separate Storm Water Sewer System) Program regulations ; require municipalities and government agencies including the Louisiana Department of Transportation and Development (LADOTD) to ; develop and implement stormwater best management practices (BMPs) for linear transportation systems to reduce the discharge of ; various pollutants, thereby protecting water quality. An efficient and cost-effective stormwater BMP is urgently needed for elevated ; linear transportation projects to comply with MS4 regulations. This report documents the development of a first flush-based stormwater ; treatment device, the first flush reactor, for use on elevated linear transportation projects/roadways for complying with MS4 regulations. ; A series of stormwater samples were collected from the I-10 elevated roadway section over City Park Lake in urban Baton Rouge. ; Stormwater treatment experiments were conducted using three laboratory columns filled with different combinations of filter medium ; layers. In terms of contaminant removal efficiency, the optimum filter medium combination was found to be (a) a mixture of Smart ; Sponge and Hydra CX2 in the top layer, (b) zerolite in the next layer, (c) sand, (d) sawdust, and (e) gravel in the bottom layer. Results of ; the laboratory experiments indicate that the first flush reactor with the optimized filter medium layers is able to remove over 85% of total ; suspended solids (TSS), 90% of total phosphorus, 99% of NO2-N and NO3-N, and 70% - 90% of fecal coliform bacteria. Tested heavy ; metals include Al, As, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Na, Ni, P, Pb, Si, and Zn. In general, removal rates of heavy metals through the ; recommended filter media are higher than 80%. The removal rates of three toxic heavy metals including cadmium (Cd), copper (Cu), and ; lead (Pb) are higher than 90%. Hydrocarbon levels in the stormwater samples were too low to be detected. Some unsolved problems in ; the current design of the first flush reactor include the low removal rate (15%-58%) of TKN (Total Kjeldahl Nitrogen) and the slight ; release (up to 20%) of toxic metal zinc (Zn) from the reactor. The problems may be resolved by conducting more column tests and ; possibly replacing the Hydra CX2 with other types of fiber mulch. Experimental results presented in this report may be used for further ; study of filter medium selection and for optimization of the first flush reactor. ; Guidelines for design, field construction, operation, and maintenance of the first flush reactor are provided in this report to help ; environmental engineers and stormwater managers design and operate the first flush reactor properly and achieve the stormwater ; pollutant removal efficiency required in the MS4 program.
  More +
• Format:
  PDF
• Funding:
  LA 736-99-1516 ; LTRC 08-3TIRE
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/17815/dot_17815_DS1.pdf
• File Type:
  [PDF - 631.69 KB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:8132f5138768ad9dd40f98b524c111aadd3e93373d4b5c231015ceb8a8a52050